"Camila gave birth to our third child yesterday morning," he wrote in a post on both sites. "Our son, Livingston Alves McConaughey was born at 7:43am on 12.28.12. He greeted the world at 9lbs. and 21 inches. Bless up and thank you for your well wishes.

"Happy New year, and just keep livin, Camila and Matthew McConaughey," the actor added.

Matthew first revealed he and Camila were expecting their third child on July 4 when he Tweeted, "happy Birthday America, more good news. Camila and I are expecting our 3rd child, God bless, just keep livin."

A little over a year ago, Matthew proposed to Camila next to the Christmas tree. The pair, who are parents to Levi, 4, and Vida, who is 3 in January, married in June of 2012.

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